The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 29, 2000
Filed:
Jul. 02, 1996
Yong Li, Kanata, CA;
Adnan Abu-Dayya, Ottawa, CA;
Hong Zhao, Nepean, CA;
Rui Wang, Ottawa, CA;
Iouri Trofimov, Moskva, RU;
Alexandre Chloma, Moskovskaja oblast, RU;
Mikhail Bakouline, Moskovskaja oblast, RU;
Vitali Kreindeline, Moskva, RU;
Nortel Networks Corporation, Montreal, CA;
Abstract
A method of carrier recovery in a wireless communications system using a known synchronization word, for example an IS-54 TDMA system, operates in two stages to produce an estimate of carrier phase. In the first stage, a complex fading factor, embodying carrier phase information, is estimated from the synchronization word in the received signal using a least square criterion. In the second stage, the carrier phase is estimated from this complex fading factor by averaging. The averaging can provide a recursive average or a moving average, or can be implemented using Kalman filtering which also provides an estimated amplitude factor and frequency shift. The method and apparatus provide a substantial improvement over phase locked loop carrier recovery.